Before I found this, I found this: https://github.com/TomConlin/MakefileViz
When I used this I found that processes themselves were not visualised. It would be quite cool if it showed the processes that were used as well in between inputs and outputs. I realise that each recipe itself would be considered a process, where the recipes call other processes. Later in the future, this can be used to visualise to create subgraphs within a larger graph.